ABSTRACT
Introduction .......................................................................................................... 44 Oil Hydrocarbon Fingerprinting Methodologies ............................................ 47
Source-Specific Target Hydrocarbons ..................................................... 47 Tiered Analytical Approach ...................................................................... 51 Revised Nordtest Methodology for Oil Spill Identification.................. 58
Level 1 ............................................................................................. 58 Level 2 ............................................................................................. 59 Level 3 ............................................................................................. 59 Conclusion ...................................................................................... 59
Two-Dimensional GC: An Emerging Technique for Fingerprinting Hydrocarbons ..................................................... 60
Chemical Composition of Oil and Petroleum Products and Spill Identification ............................................................................................... 61 Chemical Composition Features of Crude Oil ....................................... 62
Background Hydrocarbons: Distinguishing Biogenic Hydrocarbons from Petrogenic Hydrocarbons in Oil-Contaminated Samples .......................................... 64
General Chemical Composition Features of Refined Products ........... 67 Light Distillates .............................................................................. 67 Midrange Distillates...................................................................... 68 Classic Heavy Residual Fuel ......................................................... 70 Lubricating Oil ............................................................................... 70 Waste Oil ........................................................................................ 71
PAH Fingerprints of Oils and Petroleum Products ............................... 71 Distribution of Alkylated PAH Homologues and Other
EPA Priority PAHs ......................................................... 71 Recommended Diagnostic Ratios of PAHs ............................... 72 PAH Isomer and Cluster PAH Analysis ..................................... 75 Methyl Phenanthrenes .................................................................. 76 Methyl Dibenzothiophenes .......................................................... 76 Other Relative Ratios of PAH Isomers ....................................... 77
Petroleum plays an extremely important role in modern society. As the population of the world increases and developing countries become more industrialised, the demand for energy keeps growing worldwide. Just fewer than 2 billion barrels (1 barrel = 159 L) of crude oil was processed by refiners in the United States in 2004. Consumption worldwide was about 30 billion barrels in 2004. Table 3.1 presents the worldwide petroleum demand and supply from 1970 to 2004 (DOE 2004). Currently, oil is the dominant energy source and is expected to remain so over the next several decades (NRC 2002). In addition to natural seeps, which are purely natural phenomena that occur when crude oil seeps from the geologic strata beneath the seafloor to the seawater column, the worldwide extraction, transportation, and consumption of petroleum inevitably result in its release to the environment. Waterborne oil spills of unknown origin from continuous leaks or illegal discharge often occur in rivers, open waters, and coastal waterways. Petroleum and its com-
Cluster PAHs at m/z 216 ............................................................... 77 Distinguishing Pyrogenic Hydrocarbons from Petrogenic
Hydrocarbons ................................................................. 78 Biomarker Fingerprints of Oils and Petroleum Products..................... 79
Distributions and Quantification of Biomarkers ...................... 79 Low-Boiling Sesquiterpanes in Oils and Lighter
Petroleum Products ....................................................... 86 Diagnostic Ratios (Indices) of Biomarkers ................................ 89
Weathering Check Using Hydrocarbon Fingerprints ........................... 94 Oil Weathering .............................................................................. 94 Weathering Check Using n-Alkanes and GC Traces ............... 95 Weathering Check Using PAHs .................................................. 97 Weathering Check Using Biomarkers ........................................ 98
A Case Study: Using a Multicriterion Approach for Source Identification of Unknown Spill Samples .................................. 99 Product Type Screen and Determination of Hydrocarbon
Groups ........................................................................... 100 Determination of Oil-Characteristic Alkylated PAH
Homologues and Their Diagnostic Ratios ............... 102 Input of Pyrogenic PAHs to the Spill Samples ........................ 103 Characterisation of Biomarker Compounds ........................... 105
Conclusions ......................................................................................................... 106 Acknowledgements ............................................................................................ 106 References ............................................................................................................ 107
bustion-derived hydrocarbons are often some of the most frequently discovered chemicals of concern at contaminated sites on land.
